In rheumatoid arthritis, an autoimmune inflammatory disease, another member of the miR-548 family, miR-548a-3p, was significantly down-regulated in serum samples targeting Toll-like receptor 4/nuclear factor kappa B (TLR4/NF-kappaB) signaling pathway (Wang et al., 2018). Here, TLR4 is linked to rheumatoid arthritis.